[Unknown Mod][Locations] Hero can upgrade his creatures in the creature dwellings of the adventure map [Edited]

[LeHerosInconnu]

The hero can upgrade at a cost the creatures already in his army in the corresponding dwelling on the adventure map (Archer to Ranger in the Archer's Houses, etc.).

When the hero is positioned on the location's active square, the "UPGRADE" button is displayed in the creature information window in the hero's screen, allowing creatures to be upgraded at standard cost.

In fheroes2:

Creature generators on the adventure map, where creatures can be upgraded:

• Archer's House
  Allows to upgrade Archer to Ranger.
• Watch Tower
  Allows to upgrade Orc to Orc Chief.
• Dwarf Cottage
  Allows to upgrade Dwarf to Battle Dwarf.
• Troll Bridge
  Allows to upgrade Troll to War troll.
• Dragon City
  Allows to upgrade Green Dragon to Red Dragon or Black Dragon.
  Allows to upgrade Red Dragon to Black Dragon.
• City of the Dead
  Allows to upgrade Lich to Power Lich.

This is an option:
"Locations: Hero can upgrade his creatures in the creature dwellings of the adventure map"
Ot it can be implemented without being an option, as the player can simply ignore the feature to have the same experience as the original game.
This can be implemented directly in fheroes2.

Note: all of this could eventually change.